The Application Of Fountain Code Technology In Next Generation Broadcast Networks And Research Of Corresponding Protocol Stack

With the increasing development of people’s needs of material and cultural, the requierment of broadcast business is growing rapaidly. It is an effective way to guarantee massive reliable data transmission when using Forward Error Correction(FEC) technology and corresponding protocol stack. Therefore, it is with great practical value to do research on new FEC technology and corresponding protocol processing mechanism.Digital fountain code as a new FEC technology has been standardized by 3rd Generation Partnership Project Multimedia Broadcast Multicast service(MBMS) and Digital Video Broadcasting(DVB) due to its rate less encoding characteristic and flexible decoding mechanism. File delivery over Unidirectional Transport(FLUTE) is a protocol which suits for broadcast system and supports Raptor codes as its FEC feature, and it has also been used in DVB IP Datacast and 3rd Generation MBMS. In this paper, from the point view of the application of fountain codes, the decoding mechanism and its application in next generation broadcast networks are studied and several innovation points have been put forward, which can be generated listed as follow:(1) A new decoding algorithm is proposed, where the decoding delay has been cut down by 50 percent, due to the fact that decoding delay and decoding failure probability has become a serious issue in the Raptor Q code. Besides, repair decoding technology is used on the basis of the decoding procedure has been completed in the original decoding process, therefore, it avoid the unnecessary decoding delay caused by the repeat decoding procedure.(2) Raptor Q code is used as a new type of FEC code in the FLUTE protocol stack, which makes the data push system more flexible. Based on the rate less encoding characteristic and flexible decoding mechanism of fountain code, the scheme uses broadcast system to large scale data push and cellular system to point to point data repair in the Next Generation Broadcast Wireless system(NGB-W) to insure the reliability of the data push system.(3) A basic data push system mode based on the FLUTE protocol stack is proposed, in which the explicited description of each module’s basic function and design details are given. Besides, the concrete implementation scheme of sending and receiving file content in the proposed data push system is provided. At last, the corresponding parameter information of Raptor Q code is given.